diff --git a/src/mathed/math_cursor.C b/src/mathed/math_cursor.C
index 5c20087256..d7f2b8d574 100644
--- a/src/mathed/math_cursor.C
+++ b/src/mathed/math_cursor.C
@@ -1483,25 +1483,10 @@ MathCursorPos MathCursor::normalAnchor() const
 
 MathInset::result_type MathCursor::dispatch(FuncRequest const & cmd)
 {
-	// try to dispatch to adajcent items if they are not editable
-	// actually, this should only happen for mouse clicks...
-	idx_type d1;
-	pos_type d2;
-	if (hasNextAtom() && !openable(nextAtom(), false)) {
-		MathInset::result_type res = nextAtom().nucleus()->dispatch(cmd, d1, d2);
-		if (res != MathInset::UNDISPATCHED)
-			return res;
-	}
-	if (hasPrevAtom() && !openable(prevAtom(), false)) {
-		MathInset::result_type res = prevAtom().nucleus()->dispatch(cmd, d1, d2);
-		if (res != MathInset::UNDISPATCHED)
-			return res;
-	}
-
 	for (int i = Cursor_.size() - 1; i >= 0; --i) {
 		MathCursorPos & pos = Cursor_[i];
-		MathInset::result_type const res
-			= pos.par_->dispatch(cmd, pos.idx_, pos.pos_);
+		MathInset::result_type
+			res = pos.par_->dispatch(cmd, pos.idx_, pos.pos_);
 		if (res != MathInset::UNDISPATCHED) {
 			if (res == MathInset::DISPATCHED_POP) {
 				Cursor_.shrink(i + 1);
diff --git a/src/mathed/math_data.C b/src/mathed/math_data.C
index 127d09ce89..c53341d35e 100644
--- a/src/mathed/math_data.C
+++ b/src/mathed/math_data.C
@@ -66,6 +66,7 @@ void MathArray::insert(size_type pos, MathAtom const & t)
 
 void MathArray::insert(size_type pos, MathArray const & ar)
 {
+	lyx::Assert(pos <= size());
 	base_type::insert(begin() + pos, ar.begin(), ar.end());
 }
 
diff --git a/src/mathed/math_nestinset.C b/src/mathed/math_nestinset.C
index 738e89ea10..9dd85d446a 100644
--- a/src/mathed/math_nestinset.C
+++ b/src/mathed/math_nestinset.C
@@ -332,7 +332,8 @@ MathInset::result_type MathNestInset::dispatch
 
 		case LFUN_PASTESELECTION:
 			return
-				dispatch(FuncRequest(bv, LFUN_PASTE, bv->getClipboard()), idx, pos);
+				dispatch(
+					FuncRequest(bv, LFUN_PASTE, bv->getClipboard()), idx, pos);
 			
 		case LFUN_MOUSE_PRESS:
 			if (cmd.button() == mouse_button::button2)